Building a PC to run SBR+ simulation on HFSS

I suspect manufacturers were finding it difficult to clock a cpu faster than 2.5 GHz (Say 20 years ago). And experimenters who 'overclocked' often ran into problems with a cpu overheating. So manufacturers started making multiple cores.

When you have multiple cores (parallel processors, etc.), then the software should be designed to take advantage of it. Can HFSS say this? Can it discern whether you have 14 cores or 20?

It makes a difference what OS your computer runs. I have an HP laptop running Win 10, and it's doggone slow. There are people dropping back to Win 7 because of dissatisfaction with Win 10 or 11. However you must check whether your version of HFSS can run under a given OS.

Also consider installing a Linux OS version on your laptop. There are ways to run Windows applications under Linux. Linux isn't so bloated as Windows 10 & 11.

HFSS is optimized for load distribution across multiple cores. It runs on windows and linux.

That being said, the default HFSS license will only run 4 threads; you need a higher-tier license to employ more processes. Typical loads are 1-2 cores per thread, so keep it in mind that a large core count may not be too beneficial either.

From experience running HFSS across multiple compute platforms, I would say the biggest performance boost is obtained with increased memory. HFSS can never really have enough (I started with 2 GB and ended with 8 TB... it still wasn't enough).

"trim the fat off your PC" with a new login that runs like safe mode but with full graphics by disabling all startups in MSconfig for that user and many services not needed.

I can help with that.

Otherwise a lots of RAM, SSD and high CPU speed in an old tower on Win7 trimmed down or Linux will operate at reasonable speeds.

When building a PC for simulation tasks like HFSS, you need to consider both the clock speed and the number of cores, as well as other factors. HFSS is a high-performance computing application that benefits from both single-threaded performance and multi-core parallel processing.
Here are some considerations:
Processor (CPU):

1. Clock Speed:
   • Higher clock speeds generally benefit tasks that are more dependent on single-threaded performance. HFSS simulations often require good single-threaded performance for certain calculations.
2. Number of Cores:
   • HFSS can take advantage of multiple cores for parallel processing. The more complex your simulations, the more cores can be beneficial. However, the efficiency of parallelization depends on the nature of the simulation and the software's ability to distribute tasks across cores.
3. Xeon vs. Core i5:
   • Xeon processors are designed for professional and server applications, while Core i5 processors are more consumer-oriented. Xeons may have more cores but can have lower clock speeds compared to consumer-grade CPUs. The choice depends on your specific needs and budget.
4. Dual Processor Setup:
   • HFSS can benefit from multiple processors, but not all simulations scale well with dual CPUs. Check the software's documentation to see if it effectively utilizes a dual-CPU configuration.

Memory (RAM):

1. RAM Speed vs. Capacity:
   • HFSS simulations can be memory-intensive. While faster RAM can improve overall system performance, having sufficient RAM capacity is crucial. Choose a balance between speed and capacity. Aim for at least 32GB or more, depending on the size and complexity of your simulations.
2. ECC (Error-Correcting Code) Memory:
   • If stability is critical, consider using ECC RAM. It provides additional error checking and correction, which can be beneficial for long simulations where data integrity is crucial.

During years, I found that the most visible speed jump was when I increased the RAM capacity from 8Gb to 16Gb.
Also from 16Gb to 32Gb was a big speed jump but not as higher as 8Gb to 16Gb. I think after 32Gb of RAM the increased speed is coming mainly from better CPUs.